Improvement in machines for dressing millstones



W. FABROW.

Machines for Dressing MiHstones.

vNo. l42,009, PatentedAugust19,1873.

AM, PHOTO-LITHOGRAPH/G ca. mama/ E's Pnqcsss) UNITED STATES WILLIAM FARROW, OF ALEXANDRIA, ILLINOIS.

IMPROVEMENT IN MACHINES FOR DRESSING MILLSTONES.

specification forming part of Letters Patent No. 142,009, dated August 19, 1873; application filed July 11, 1873.

To all whom it may concern:

Be it known that I, WILLIAM FARROW, of

Alexandria, county of Warren and State of class of millstone-dressing machines in which any ordinary pick is used, and motion given thereto by a machine driven by hand-power; and the invention consists in the arrangement of a reciprocating frame within a stationary frame, the said reciprocating frame being provided with shafts, a crank, and with pinionwheels, which engage with a toothed bar on the stationary frame, allowing the said reciprocating frame to be driven forward and back while it carries with itself suitable'devices for operating the pick, which it also carries, the pick-handle being pivoted to a shaft on the reciprocating frame in such manner that it may be reciprocated laterally by a handle provided for the purpose, all as hereinafter fully described.

In the accompanying drawings, Figure 1 represents a side elevation of my invention, and Fig. 2 is a top plan or view, partly broken away to show the parts more fully.

Referring to the parts by letters, letters A represent the main frame, formed of top, bottom, and end pieces, as shown in the drawings, and with horizontal side frame pieces A A, on which are secured rack-bars ,B B. Letters 0 represent the reciprocating frame,

formed of posts 0 0 O (3, connected by transverse bars 0 G C C, and longitudinal bars Q C G G G O. D is the main drivingshaft, carried in suitable hearings in the side frame pieces G O, and provided with a crank, d, at one end. E is a shaft parallel with the shaft D, and is provided also with suitable bearings in the side frame pieces 0 G, and carries on its ends pinion-wheels e e, which engage with the rack-bars B B, and is also provided near one end with a larger gearwheel, G. H is a shaft, crank-shaped, as

shown at Fig. 2, and provided at one end with a pulley, 7b, which is geared by a band, I, to a pulley, d, on the main driving-shaft D, J

is a tappet projecting from one side of the shaft H. K is the pick, secured to one end of shaft L, the other end of which is provided with an eye fitting loosely but snugly upon a transverse shaft, M, which extends across,

and is secured to, the lower part of the frame 0. N is a pitman or connecting rod, adjustably attached at its upper end to the crank shaft H, and pivoted at its lower end within a slot in the shaft L, where it may be adjusted longitudinally to the shaft L by a pin in the series of holes n n. P is a spring, secured at one endto one of the side frame pieces 0, and its free end resting on the end of pin 19, which passes loosely through one of the side frame pieces 0, and impinges against the face of the wheel Gr. 7

The operation of my invention is as follows: The machine is stood upon the stone to be dressed, and it will be evident that the crank being turnedfor instance, to the right-will give motion to the pick by the crank-shaft H, and that at each revolution of the shaft H the tappet J will engage with atooth or cog of the wheel G and rotate the shaft E and pinions 0 e a short distance, thereby moving the entire frame (3, and with it the pick K, backward until the end of the rack-bars B B is reached by the pinions e 0, when, by reversing the direction of the crank d, the frame 0 may be carried back in the opposite direction, and the operations of the pick be continued at the same time, the end of the pin p resting with sufficient pressure against the face of the wheel G to prevent it turning farther at each impulse it receives from the tappct J than what it is moved while in contact with said tappet. It will be evident that by this operation a succession of rapid and exactly uniform blows may be struck by the pick, while it is at the same time steadily and regularly advanced or drawn backward over the face of the stone. A motion may be given to the pick sidewise or laterally, when desired, or it may be adjusted laterally on the shaft M by means of a bar, It, which is provided with a handhold on its upper end, and is bifurcated and placed astride of the rear end of the pick-handle or shaft L, at its lower end, and the pick PATENT OF IoE.

may by the same means be held securely from lateral displacement when in operation, and when desired.

I claim 1. The reciprocating frame (J, when arranged to operate with the stationary frame A, by means of shafts D, and E, and H, pinions e 0, rack-bars B, and pulleys d and'h, substantially as described, and for the purpose specified.

2. The pick K, shaft L, pit-man N, and crankshaft H, when combined and arranged to operate substantially as described, and for the purpose specified.

3. The bar B, when arranged to operate with the shaft L, and with the transverse shaft M, substantially as described, and for the purpose specified.

WILLIAM FARROW. Witnesses:

JOSEPH STAFFORD, GEO. C. BUELL. 

